Apparatus for mixing



Oct. 31, 1950 J, G .sUTHA-RD TAL 2,527,689

APPARATUS FOR MIXING Filed Deo. 11, 1946 ROBE/Q7 A Poel/vaan By THE/R A Wbp/vers Patented Ot. 31, 1950 APPARATUS FOB HIKING JamesG. SntharlandltobertLlhHnsomLcng Petrolite Beach,

'tiomLtlLWll-lington,

Delaware Calihamlgnonto Corpora- Maccrporaiicnct Application December ll, 194C, Serial No. 715,52.

- l Ourinventionrelatestothemixingoi'dissimilar and substantially immiscible liquids to produce suspensions, e. g., dispersiom or emulsionsofmoreorlesspermanency. Itwillbe particularly exempliiied as applied to thev synthesizing oi' water-in-oil type emulsions, the word water being herein used as including any aqueous medium or aqueous solution sumciently immiscible with the oil to form a separate phase when mixed therewith.

Ifamassofwaterandamassofoiiareintermixed, the resulting suspension or emulsion may be of the oil-ln-water or water-in-oil type or a mixture of these two types, depending upon the relative volumes, the type of mixing and the emulsiiying or dispersing agents present.

In the processing of oils. typically in their purincation, it is often desirable to produce synthetic suspensions of the water-in-oil type. It has been proposedtodothisinacontinuomprocessby pumping streams of oil and water together to form a preliminary mixture which is then forced through a mixing valve. 'I'his requires high pressin'ing of both streams and involves relatively high pumping costs as the pressure drop across the mixing valve is usually relatively high to produce the desired mixing action.

It is an object of the invention to minimize the power required to mix two liquids. In the production of water-in-oil type suspensions or emulsions, the volume of water is usually substantially less than the volume of oil. According to the present invention only the smaller stream of water need be substantially pressured with re-v sulting savings in power requirements.

It has been found that mixing' systems, such as described above, or other conventional mixing apparatus are oftentimes decient if a suspension or emulsion substantially exclusively of the water-in-oil type is desired. .In conventional systems, a small amount of "inverse phase is often formed, i. e., a quantity of oil-in-water type suspension or emulsion existing inthe desired water-in-oil suspension or emulsion. For example, droplets of water may be dispersed in a continuous phase of oil but these droplets may themselves carry dispersed droplets of oil. Such dispersions of oil droplets in water are generally referred to as inverse phase emulsions in the petroleum dehydration and desalting arts.

The presence ofsuch inverse phase, even in smallquantities, is often troublesome in resolving suspensions or emulsions which are essentially of the water-in-oil type. Such resolution lzchmis. (m. :5s- 4) 2 l 1 persed water droplets. Any oil droplets dispersed inthe water droplets will appear in the coalesced water'masses and be carried downwardly thereby as they gravltate to and join with the body of separated water in the lower portion of the settling sone. This'contaminat the body of separated water, prevents a clean separation of the oil'and the water and mises a serious dispbsal problem `due to the oil content of the water drawn from the settling sone.

Substantiallyv the same dimculties arise in processes in which the emulsion is subjected to Vthe action of a high voltage electric eld to aid in the coalescence oi.' the water droplets and in the resolution of the emulsion. .In addition, the

presence of any inverse phase presents-additional dimculties in the electric treatment of emulsions.

If present in large amounts,such inverse phase may short-circuit the treating electrodes or unduly increase the current therebetween. Even l if present in minute quantities, such inverse phase is not directly resolved by the electric iield because oil droplets dispersed inthe water cannot be subjected to electrically induced coalescing forces because of the conducting nature of the water. It would be very desirable to eliminate or minimize the amount of inverse phase present in any water-in-oil emulsion or suspension.

It is an important object Voi' the invention to provide a process and apparatus for the synthesizing of water-in-oil type suspensions or emulsions while minimizing or completely eliminating the forming of objectionable amounts of inverse agents tendto promote the oil-in-water type oi' emulsion but which tendency is repressed or nulliiled by the method of mixing employed in the invention. I

In accordance with the preferred mode of operation of the present'invention, one liquid, e. g., water, is discharged as a radial or conical spray or thin sheetinto a coniined stream of the other liquid, e. g., oil, as this other liquid moves along a space. Such a procedure produces a uniinvolves a coalescence and separation of the dis- 55 munity 0I distribution of the water in the oil.

which is not possible with other mixing devices used in the art. Also, it permits control of the particle size oi the aqueous dispersed phase by adjustment of the spray pressure and control of the force of the spray required to penetrate or cut through oils of difl'erentviscosity. The preferred apparatus also permits control of the thickness or velocity of the spray from a position removed from the spray 'and external to the space into which the spray discharges. It is an object of the invention to provide a process and apparatus for mixing which has this mode of operation and one or more of the above advantages.

Still other objects of the invention are to produce a mixing system which does not change its mixing action due to scaling of pipes, such as occurs with many conventional systems when/,

mixing certain oils with water; .which is readily adjustable to change the degree of dispersion; which can be made to produce a suspension or emulsion having a particle size distribution diilering from suspensionsor emulsions made by conventional apparatus; which substantially instantaneously produces the desired type of suspension or emulsion; or which avoids the presence of any large masses or bodies of water at the.point of mixing.

One widely used method for desalting or otherwise purifying mineral oils of low water content involves emulsication of water with the oil and resolution of the resulting emulsion by use of chemical demulsifying agents, heat and pressure settling, or subjection to a high-voltage coalescing electric iield in an electric treater. If the impure oil contains a small amount of dispersed water, e. g., residual brine droplets, best results are usually obtained by dispersing the added water into the oil to produce droplets of the added water coexisting with the originally present droplets. The present mixing apparatus is excellently suited to the production of emulsions of this type and emulsions which are unusually well adapted to such electrical puri- In the electrical desalting of pared with the use of conventional mixing valves for forming the emulsion. It is an object of the invention to provide an improved process for desalting or purifying oils.

Another process in which the invention is particularly useful is that in which an oil containing organic acids is mixed with an aqueous alkaline solution thereby producing a sodium soap when the two liquids come into intimate contact. Such soaps are in general very effective stabilizing agents and, if the mixing is by ordinary means, will definitely promote the formation of oil-in-water type emulsions. However, the method of the invention provides nc opportunity for the oil to become dispersed in the aqueous solution so that the formation o! the oil-in-water type of emulsion -is greatly repressed, if not entirely eliminated particularly if the volumetric ratio of the aqueous phase to the oil phase be kept reasonably low, usually below about depending to a considerable extent upon the amount and kind of acidic materials present in the oil, as well as somewhat upon the structure of the mixing device.

Further objects and advantages of the invention will be evident to those skilled in the art from the following description of exemplary embodiments.

Referring to -the drawing:

Fig. 1 is a. diagrammatic view showing one embodiment of the mixing apparatus of the lnvention as used in association with other puriilcation equipment;

Fig. 2 is a longitudinal sectional view of the mixing apparatus of Fig. l;

Fig. 3 is an enlarged sectional view taken along the line 3-3 o! Fis. 2;

Fig. 4 is a sectional view taken along the line 4-4 of F18. 3;

Fig. 5 is a longitudinal sectional view of an alternative form of spray unit;

Fig. 6 is a fragmentary sectional view of a further alternative spray unit head; and

Fig. 7 diagrammatically illustrates an alternative biasing means which can be used with any of the illustrated embodiments.

Referring particularly to Fig. l, the mixing apparatus of the invention, indicated as 9, mixing unit I0. functions to mix oil supplied by pipe Il and water supplied by pipe I2. The invention will be exemplified as used in a purification process to emulslfy the water into the oil, the emulsion being resolved in a suitable treater Il illustrated as equipped with upper and lower electrodes I8 and I1. These electrodes are insulated from each other and a high-voltage electric held is established therebetween by any suitable power source, not shown. This field coalesces the dispersed water droplets of the emulsion into masses of suilicient size to gravitate from the oil and form a body of separated water 20 in the lower end of the treater and a body of purified oil 2l in the upper end of the treater. In a continuous process, streams of oil and puriiied water are drawn respectively from the bodies .through draw-off pipes 22 and 23 equipped with valves to build up a desired back pressure in the treater l5, typically 25-50 p. s. i. The emulsion enters the treater I 5 through a pipe 25 and is discharged radially outward between the electrodes I8 and I1 through a distributor 28. Such treaters and their use in the electrical puriilcation of oils are described in the patent to Harold C. Eddy No. 2,182,145.

In other instances, non-electric treating or resolution systems can be employed to treat or resolve the suspension or emulsion made by the mixing unit l0. For example, the treater II may be employed merely as a settling zone which permits gravitational sedimentation of the water from the oil with or without previous subjection of the emulsion to some coalescing action aided, for example, by the addition of known deemulsifying or chemical treating agents. Resolution in any of such processes is usually aided by superatmospheric temperature and pressure in the treater I5. With some oils gravitational sedimentation under controlled conditions of heat and pressure will produce a satisfactory resolution, particularly where an extremely high degree of puriiication is not required.

Heretofore it has been proposed, in such puriilcation processes, to employ separate high-pressure pumps on the oil and water pipes Il and I2 to pump the streams together at a. pressure considerably in excess of that desired in the treater Il. The oil and water, usually prelimlnarily mixed at their. point of contact, pass together through a mixing valve in the pipe 25. The pressure drop across the mixing valve is often about 20-60 p. s. i. and such conventional systems require pressuring of both the larger-volume oil stream and the smaller-volume water stream to '5 y a value equal to or somewhat above the pressure .on the intake side of the mixing valve. The pressuring of large-volume oil streams is costly both in equipment and operation and the pumps employed often tend further to emulsify the oil with the water initially present therein, thus making subsequent removal of the water even more dlfncult.

Generally speaking, the present invention requires relatively high pressuring ofthe water stream only, the oil stream being pressured only to such extent as to cause it to ilow to the treater I I against any pressure existing therein. It contemplates the violent jetting of the water into a lower-pressure stream of oil to form the desired suspension or emulsion. The preferred mixing means jets or sprays the water into an annular stream of the oil as a high-velocity, thin, radially-ilowing annular stream, the ilow being inward. or outward relative to the oil stream, the

. latter being preferred, and the now being termed as radial irrespective of whether the water discharges in an exact radial plane or as a cone.

In the preferred mixing means, suggested in Figs. 1-4,.the oil in oil pipe II, owing at relatively low pressure, is delivered to a pipe T 30. Connected to one side passage of this T 30 by a nipple 3| and a ange 32 is a tubular member 33 which may be merely a continuation of the pipe or which may be of slightly larger diameter than this pipe. The other side passage of the`pipe T contains a removable plug 34 having a neck 35, this structure providing a water-conducting passage 36.

The neck is threadedly received by one arm of a cross-type pipe fitting 33. The water or other liquid which is to form the dispersed phase, moves from the pipe I2 to the intake of a pump where it is pressured and delivered through pipes 4l and 42 and T tting 43 to the interior of the cross-type pipe fitting 33.

The plug 34 carries an inner tubular member or pipe 45 which is coaxial with the tubular member 33. 'Ihe pipe 45 is smaller than the nipple 3l and the tubular member 33 and cooperates therewith in providing an annular space 46 through which the oil from pipe I I moves as an annular stream in the direction of arrows 41 of Fig. 3.

To discharge the water radially outward into the annular oil stream, the inner end of the pipe 45 carries a spray-type distributor 50 including` generally speaking, a seat member 5I threaded into the end of the pipe 45 and a head member 52, these members cooperating in defining an like spray or annular stream which discharges substantially uniformly at all peripheral positions. It is desirable also that wear, produced by relative movement of the members 5I, 52 or erosion or corrosion thereof by the water, be minimized. The spray-type distributor of Figs. 2 4 is designed particularly to accomplish these results.

As there shown, the head member 52 provides a stem in which peripherally-disposed longi- `tudinal grooves Ilv are cut. The peripheral zones between the grooves 5l are built up by coatings 51 of a hard, corrosion-resistant alloy such as stellite. 'Ihe seat member Il' provides an opening 59 which is internally coated throughout a portion or all of its length with a similar hard, corrosion-resistant alloy. In the structure shown, two axially-spaced bands of such an internal vcoating are employed, such bands or coatings being indicated by the numeral 50. The outer peripheries of the coatings 51 and the inner peripheries of the coatings 50 are ground to a sliding ilt. The grooves 55 thus form a plurality of longitudinal passages 5I and the pressured water in the pipe 45, flowing as indicated by the arrow 52 of Fig. 3, divides between the longitudinal passages 6I. The resulting streams are delivered to and combined in an annular chamber 64, formed at the junction of the stem 55 and a ange or head 65 of the head-member 52. The inner portion or entrance end of the annular oriilce 53 opens on the annular chamber 54 and this chamber serves to equalize the distribution of water to the inner periphery of the orifice. The outer portion or exit isid of the orifice 53 opens on the annular space To insure long life and equal peripheral discharge, the forward end of the seat member 5I and the rear face of the head 55 provide walls 55 and 51 formed of stellite or other hard, corrosion-resistant alloy. 'I'he faces of these walls 55, 51 are accurately ground or lapped together.

' 'I'he annular oriilce 53 is bounded by such walls and will be of uniform width around its periphery and at all radial positions within the orifice. The orifice acts as a narrow slit which receives the pressured water and forms same'into an annular stream or fan-like spray which discharges into the annular space 45, and into the annular oil stream moving therein, to form substantially instantaneously the desired suspension or emulsion. The water is projected from the orifice 53 with suiilcient velocity and under sufllcient force to penetrate the oil stream and be dispersed as small droplets therein.

It is often desirable that the oil should move with turbulent flow through the annular'space 45 so as to be moving turbulently at the instant the water is projected thereinto. Such turbulent ow can be insured by correlation of the size of the annular space 46 relative to the relatively high velocity and the viscosity of the oil therein. Also, turbulence can be insured or lincreased by making the outer diameter of the orice 53 smaller than the pipe 45, as suggested in Figs. 2 and 3. It should be clear, however, that the invention is not limited to this size relationship.

In the preferred arrangement, the head member 52 is resiliently urged toward closed-orifice position. We prefer to exert a pull on the stem 55 through a flexible eonnnector such as a uni'- versal joint, indicated generally by the numeral 15. As shown, this includes a forward universal joint element 1I having a tongue 12 extending into a groove at the rear of the stem and journalling therein about a pin 13. The rear end of the element 1I is bifurcated and receives a tongue 14 of a rear universal joint element 15, the tongue 14 being journalled on a pin 15 extending at right angles to the pin 13.

The rear universal joint element 15 threadedly receives and is locked to a rod 18 which extends centrally along the pipe 45, the plug ,34 and its neck 35 and into and through the chamber ofthe cross-type pipe tting 38. In this connection the rod 13 extends throughsl nipple 15 and through a stuiling box 55 detachably connected to the nipple by a nange' 5|. Arms 52 extend rearwardly from the stumng box and support a plate 53 threaded to receive a gland orv adjustment member 54 which is passaged to accommodate the rear end of the rod 15. The rear end of this rod carries a. head 55. A compression spring 55 is compressed between this head and the adjustment member 54 to exert a resilient biasing force on the rod which urges the head member 52 toward closed-oriiice position. A coupling 55 may be disposed between the ends of the rod 15, preferably in the space bounded by the arms 52, to adjust the over-all length of the rod and the biasing action of the spring 55 if the coupling is of the turnbuckle type. Usually, however, the adjustment of the biasing force is accomplished by turning the adjustment mmeber 54 to change the spring tension without changing the over-al1 length of the rod 15.

The biasing means thus far described will produce .satisfactory results without additional control. However, as a further renement, it is sometimes desirable to keep the pressure drop across the annular orifice 53 substantially constant with change in the amount of water introduced or change in the pressure thereof. In this instance the rear end of the rod 15 may be pressure operated by the system suggested in' Figs. 1`

and 2. Here a stationary member or housing 52 cooperates with a movable member or diaphragm 83 in providing a chamber 54 communicating.

with the pipe T 43 through a small pipe 55. lf a valve 55 in this small pipe is opened, the pressure of the incoming water will be indicated on a gage 91 and transmitted to the chamber 54. By connecting the diaphragm 53 to the head 55, any.superatmospheric pressure in the chamber 54 will reduce the action of the spring 55 on the rod 15 and decrease the biasing force applied to the head member 52. Thus, if the pressure or volume of the water stream increases, the bias on the rod 15 will be decreased and the annular oriiice 53 will open slightly, as compared with its previous width, with the result that the water pressure in the pipe 45 ahead ofthe spray-type distributor 55 will be reduced and the pressure drop across the orice 53 will be maintained approximately f constant. correspondingly. if there are to be substantial variations in pressure or amount of the water mixed with the oil, use of such a pressure operated system willeliminate any manual adjustment of the biasing force such as would otherwise be necessary if it were desired to maintain the pressure drop across the orifice 53 substantially constant.

If desired, the cross-type pipe fitting 35 may be provided with a drain pipe 55 normally closed by a valve 55.' This valve is opened only when it is desired to drain the water from the system. In the alternative, embodiment of Fig. 5 a tubular member |55 surroimds a pipe |55 providing a modified form of spray-type distributor I i0. As before, oil from a pipe flows along an annular space ||2. Water issuppl ied from a pipe ||3 toa T-like fitting ||4 which threadedly receives the rear end of the pipe |55. A packing gland structure ||5 guides and seals a rod |20. The forward end of this rod receives a screw |22 which fixes a head member |23 to the rod.

The head member A|23 is a part of the spraytype distributor ||54 which includes also a seat member |24 threadedinto the forward end of the pipe |55 and providing a neck |25. The forward end of the seat member |24 provides a radial wall |21 which cooperates with a radial wall |25 of the head member |23 to denne the annular discharge oriiice |35.

In this embodiment the rod |25 is splined to provide longitudinal passages |33. Radial guide members |34, secured to the pipe |55, extend into these longitudinal passages to prevent turning of the rod |25.

The forward end of the rod |25 slides relative to the seat member |24 and its neck |25 to center the head member |23 and prevent sidewise motion or chattering thereof. lThe longitudinal passages |33 permit free flow of the water. If desired the neck |25 may provide openings |35 respectively aligned with the longitudinal passages |33 to deliver water thereto.

The head member |23 i's biased toward closedoriiice position by a spring |31 compressed between the gland structure ||5 and a head or nut |35 of the rod |25. The biasing force can be adjusted by turning the nut |33.

In the embodiments of Figs. 1-5, the mid-plane of the orince is perpendicular to the direction of oil ilow, but this relationship is not essential to the invention. Any radial discharge of the water, whether the now be in a ilat plane or of a conical shape, can be used if the direction of discharge is'transverse to the direction of -ilow of the recipient stream, `e. g., the oil stream. In this connection, the word transverse" is used in a broad sense as defining any motion in a direction extending across the recipient stream, whether or not at a right angle to the direction of tlow of this recipient stream.

A conical-type stream is produced by the spraytype distributor of Fig. 8. This is similar to the embodiment of 5 except that the wall |21 of the seat member |24 is conical, as is also the wall |25 of the head member |23. As a result, the annular orifice |35 forms a conical stream owing transversely of the oil stream moving along the 'annular space ||2.

The rod, in any of the embodiments, can be biased by means other than a spring. For example, a weight-type bias is suggested in Fig. 7, a bell crank |55 providing one arm pivoted to the rod and another arm carrying a weight |5|, the bell crank being pivoted to any stationary structure at |52.

The operation o! any of the embodiments o! the invention will be apparent from the following description of the operation of the structure shown in Figs. 1-4.

Assuming, for example, that the apparatus is to be used for the electrical desalting of a mineral oil of low water content, a stream of this oil, commonly 'available at a relatively low pressure, say, 25 p. s. i., or pressured to this value, is delivered to the pipe Il for flow as a high velocity annular stream along the annular space 45. A substantially smaller-volume stream of relatively fresh water is pressured by the pump 45 to about 50-120 p. s. i. above the oil pressure.

annoso small particles. 'Ihe discharge velocityy should carry the water at least partially across the oil stream and any turbulent now in the annular space It or therebeyond will mix the resulting suspension with any outer portion of the oil stream which may not have been penetrated by the water. In other instances we have used with success pressure sufilcient to force the water completely across the annular space 46. Such a mode of operation can be observed in a transparent system, e. g., where the tubular member 3l is made of glass, or its ypresence can be verilied by other tests. The desired type of suspension or emulsion is made practically instantaneously and at a position adjacent the point of injection.

For best results` the annular orifice 5I should be very narrow as compared with its length,

v here its outer circumference. When this is the case, mixing of the oil and water never takes place in the presence of any large mass of water,

' thus eliminating or minimizing formation of inverse Uusually the width of the oriilce is desirabIy-less than 5.0% of vits length and sometimes as low as 0.8% of the peripheral length or lower.

In the electrical desalting process, there is no necessity for additional, water-subdividing mixing of such a suspension or emulsion before delivery to the electric treater. In fact. it is usually desirable to avoid any later mixing which would subdivide the dispersed water particles produced in the mixing apparatus of the invention. The

pressure of the resulting suspension or emulsion need be only suillcient to force same into the electric treater and maintain the desired pressure therein. Thus, in the instant example, the 25 p. s. i. oil stream can be employed to maintain a pressure of p. s. i. or somewhat more in the treater l5 if there is no large drop in pressure during ow through the distributor 26. The advantage of being able to highly pressure only the smaller water stream is of distinct value in reducing costs. In addition, the apparatus of the present invention has the advantage that the oil and water do not move together through a mixing orifice designed to produce the emulsion, thereby lessening inverse phase, producing a more easily treatable emulsion, reducing sludge accumulations in the treater, substantially eliminating oil contamination of the separated water withdrawn from the treater and producing the other desirable results previously mentioned.

Substantially the same advantages arise from non-electrical resolution systems employing the mixing device of the invention. This is true whether the invention is used to mix relatively fresh water with a salty oil in a desalting process or whether it is used to mix water with other oils to remove water-wettable and/or .water soluble impurities which can be taken up by the water and which will appear, in large measure, in the body of separated water. It is also true if the water contains chemical agents reactive usuauy be' found sumcient and a wm be found that the qantity of inverse phase will be substanmade without departing from the spirit of the y invention as defined in the appended claims.

We claim as our invention:

l. In an apparatus for. mixing two dissimilar liquids to form a suspension, the combination of a low-pressure pump for discharging a stream of one of said liquids; a tubular member connected to said low-pressure pump to receive and confine said stream; a discharge means comprising a narrow annular slit opening on the interior of said tubular member, the mid-plane of said slit being substantially transverse to the direction of flow of said stream; and a high-pressure pump for delivering a stream of the other of said kliquids to said slit to produce a high-velocity annular stream of said other liquid discharging into said confined stream of said one liquid movl ing in said tubular member.

g in defining an annular space; a spray-type diswith the oil or some component thereof, i. e., in u means for `mounting one of said walls to move the alkali treatment of oils to remove naphthenic acids or the acid treatment of oils to remove those components which can be taken up by sulphuric acid, for example. In many instances the present invention makes less critical the amount of chemauch acid or alkali treating processes pressure tributor carried by said inner tubular member and comprising annular walls facing each other and cooperating to define an annular slit having an entrance end communicating with the interior of said inner tubular member and an exit end concentric with the axis of said outer tubular member and directed toward said outer tubular member; means for delivering a stream foil under relatively low pressure to saidrouter tubular member to flow along said annular space past said exit end of said slit; and means for delivering to said inner tubular member under high pressure a stream of water to flow to said entrance end of said annular slit and thence through said slit at high velocity to be projected into said stream of oil as the oil passes said exit end of said annular slit. v

3. An apparatus for mixing two dissimilar liquids to form a suspension in which one of the liquids is substantially exclusively the continuous phase and the other of the liquids is substantially exclusively the dispersed phase, which apparatus includes: a tubular member for confining a vstream of said one liquid; means for jetting a stream of said other liquid into said tubular member at high velocity and into said one liquid flowing therein, said means including walls defining a narrow annular slit opening on the interior of said tubular member and concentric with the axis of said tubular member for forming said other liquid into an annular stream;

drops across the orifice of 50-100 p. s. i. will 7;, pressure in said chamber in response to changes in the pressure of said other liquid to move said movable member in response to such changes in pressure; and means for operatively connecting said one of said walls to said movable mem-y ber of said pressure-responsive means to vary the width oi' said slit in response to changes in pressure of said other liquid.

4ta-An apparatus as deilned in claim ain which said means for operatively connecting said one oi' said walls to said movable member includes a rod, and including a spring and a means for operatively connecting said spring to said rod to exert a spring-induced pressure thereon in one direction to bias said one of said walls toward closed-slit position. said movable member of said pressure-responsive means exerting a pressure on said rod in an opposite direction upon increase in said pressure in said chamber.

lar member outwardly at high velocity into said` annular space and into the annular stream of said one liquid owing therein, said meam including walls defining a narrow annular slit having a periphery concentric with said tubular members and means for supplying said other liquid at high pressure to the interior of said inner tubular member to ilow therealong to saiciA annular slit.

6. An apparatus for mixing two dissimilar liquids to form a suspension in which one of the liquids is substantially exclusively the continuous phase and the other of the liquids is substantially exclusively the dispersed phase, which apparatus includes: outer and A inner tubular members spaced to define a narrow annular space adapted to conne an annular stream of said one liquid to ilow therein at high velocity; a spray-type distributor at one end of said inner tubular member g and positioned within said outer tubular member,

said distributor comprising a peripherally-con-` tinuous annular orifice communicating with the interior of said inner tubular member for conducting said other liquid therefrom while forming same into a high-velocity stream, said oriilce being directed toward said outer tubular member and the periphery of said oriilce being concentric with said inner tubular member; and means extending within said inner tubular member for controlling the width of said annular oriilce.

7. A mixing apparatus as deilned in claim 6 in which said distributor includes a movable head member in the path of ilow of said other liquid and providing a wall, and a seat member providing another wall, said walls deilning said orifice, and in which said controlling means includes a rod means extending from the other end of said inner tubular member and connected to said head member, a gland at the junction oi.' said rod means and said other end oi'f said inner tubular member, and means outside said inner tubular member for adjustably tensioning said rod means.

8. An apparatus for mixing two dissimilar liquids to form a suspension in which one oi' the liquids a substantiauy exclusively the continuous phase and the other oi the liquids is substantially exclusively the dispersed phase, which apparatus includes: an outer tubular member for conilning a stream oi' said one liquid; an inner tubular member concentric with said outer tubular member and providing a seat member having an annular wall, said outer tubular member being only little larger in internal diameter than the external diameter of said inner tubular member to form a relatively narrow annular space through which said stream of said one liquid ilows at high velocity; a head member having an annular wall, said walls facing each other and cooperating to deilne an annular slit;

, means for mounting said head member to move toward and away from said seat member to vary the width of said annular slit; means for supplying to said inner tubular member a stream of said other liquid under high pressure, said slit discharging toward said outer tubular member to project a narrow annular stream of said other liquid into the stream of said one liquid ilowing along said narrow annular space and past said slit to be broken into small droplets by such now; and means within said inner tubular member adjacent said slit for slidably journalling said head member relative to said seat member to maintain the-width of said annular slit equal at all peripheral positions during such relative movement.

9. An apparatus for mixing two dissimilar liquids to form a suspension in which one oi the liquids is substantially exclusively the continuous phase and the other of the liquids is substantially exclusively the dispersed phase, which apparatus includes: an outer tubular member for conilning a stream of said one liquid; an inner tubular member providing an inner end and an outer end; mounting means for mounting said inner tubular member with its outer end outside said outer tubular member and with its inner end concentric with and inside said outer tubular member to deilne a narmw annular space between said tubular members, said mounting means closing one end of said annular space; a seat member carried by said inner end of said inner tubular member and providing an annular wail; a head member providing an annular wall, said walls facing each other and cooperating to deiine an annular orifice communicating between the interior of said inner tubular member and said narrow annular space and directed transversely of said annular space; means for mounting said head member to move relative to said seat member to change the width of said annular orifice; biasing means outside both of said tubular members; means extending along the interior of said inner tubular member and from said outer end thereof for operatively interconnecting said head member and said biasing means for biasing said head member toward closed-orifice position; and supply means for supplying to said inner tubular member a stream of said other liquid under high pressure, said oriilce discharging a narrow annular stream of said other liquid into the stream of said one liquid owing along said narrow annular space to effect the mixing of said liquids.

10. An apparatus as denned in claim 9 in which said supply means communicates with said inner tubular member at a position between said mounting means and said biasing means.

1l. An apparatus for mixing two dissimilar liquids to form a suspension in which one oi the liquids is substantially exclusively the continuous phase and the other of the liquids is substantially exclusively the dispersed phase, which apparatus includes: an outer tubular structure providing a sidewardly-directed opening; an inner tubular structure providing inner and outer ends; a mounting means for mounting said inner tubular structure with its outer end outside said outer tubular structure and extending beyond said mounting means and with its inner end within and concentric with said outer tubular structure to define an annular space therebetween, said sidewardly-directed opening communicating with said annular space at a position near said mounting means for conduction of a stream of said one liquid moving along said annular space; a seat member carried by said inner end of said inner tubular member and providing an annular wall; a head member providing an annular wall, said annular walls facing each other and cooperating to define an annular orice communicating between the interior of said inner tubular structure and said annular space, said oriilce being directed outwardly of said annular space; rod means operatively connected to said head member and extending along the interior of said inner tubular structure past said mounting means and from said outer'end of said inner tubular structure; sealing means at the junction of said rod means and said outer end of said inner tubular structure; means for 14 12. An 'emulsifying means for synthesizing resolvable emulsions which are substantially exclusive oi' the water-in-oil type and particularly suited to resolution by subjection to coalescingV electric fields in being substantially devoid of inverse-phase emulsion of the oil-in-water type, said emulsifying means comprising: walls deilning a long, narrow oritlce having a width less than 5% of its length; pump means for delivering to said oriilce an aqueous liquid which is to compose the internal phase of the emulsion to be formed, said oriilce projecting a high-velocity stream of said aqueous liquid from said orice in a given direction; a wall spaced equidistant from all portions of said orifice to define a narrow space; and a relatively low-pressure pump for delivering a relatively high-volume stream of oil to said space, the narrow -width of said space causing said oil to ilow at high velocity past said slit to shear droplets of the aqueous liquid from the stream thereof issuing from said oriilce.

JAMES G. SUI'I-IARD. ROBERT A. ROBINSON.

. REFERENCES LcrrEDy The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 519,083 Garrison May 1, 1894 1,112,416 Sargent Sept. 29, 1914 1,406,791 Werner Feb. 14, 1922 1,668,136 Agthe May 1, 1928 2,003,827 Esterling June 4, 1935 l 2,124,580 Lavine June 26, 1938 2,332,535 Rose Oct. 26, 1943 2,393,328 Mahone Jan. 22, 1946y 2,443,646 Turner June 22, 1948 

